Disable folder UI when app sync is disabled

ui/app_list/views/app_list_main_view.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_APP_LIST_VIEWS_APP_LIST_MAIN_VIEW_H_
 #define UI_APP_LIST_VIEWS_APP_LIST_MAIN_VIEW_H_
 
 #include <string>
 
 #include "base/memory/scoped_vector.h"
@@ skipping 47 matching lines @@
   void OnStartPageSearchButtonPressed();
 
   SearchBoxView* search_box_view() const { return search_box_view_; }
 
   // If |drag_and_drop_host| is not NULL it will be called upon drag and drop
   // operations outside the application list.
   void SetDragAndDropHostOfCurrentAppList(
       ApplicationDragAndDropHost* drag_and_drop_host);
 
   ContentsView* contents_view() const { return contents_view_; }
+  AppListModel* model() { return model_; }
 
   // Returns true if the app list should be centered and in landscape mode.
   bool ShouldCenterWindow() const;
 
  private:
   class IconLoader;
 
   void AddContentsView();
 
   // Loads icon image for the apps in the selected page of |pagination_model_|.
@@ skipping 36 matching lines @@
   ScopedVector<IconLoader> pending_icon_loaders_;
 
   base::WeakPtrFactory<AppListMainView> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AppListMainView);
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_VIEWS_APP_LIST_MAIN_VIEW_H_